Add functions to apply replacements and reformat them.

This is a commonly useful feature to have, and we have implemented it
multiple times with different kinds of bugs. This implementation
centralizes the idea in a set of functions that we can then use from the various
tools.

Reverts r262234, which is a revert of r262232, and puts the functions
into FOrmat.h, as they are closely coupled to clang-format, and we
otherwise introduce a cyclic dependency between libFormat and
libTooling.

Patch by Eric Liu.

llvm-svn: 262323

3 files changed, 65 insertions, 1 deletions

diff --git a/clang/unittests/Format/CMakeLists.txt b/clang/unittests/Format/CMakeLists.txt
index 01af435fffc..de26a4704a8 100644
--- a/clang/unittests/Format/CMakeLists.txt
+++ b/clang/unittests/Format/CMakeLists.txt
@@ -13,5 +13,6 @@ add_clang_unittest(FormatTests
 
 target_link_libraries(FormatTests
   clangFormat
+  clangFrontend
   clangToolingCore
   )
diff --git a/clang/unittests/Format/FormatTest.cpp b/clang/unittests/Format/FormatTest.cpp
index 164909f8688..4872565e04a 100644
--- a/clang/unittests/Format/FormatTest.cpp
+++ b/clang/unittests/Format/FormatTest.cpp
@@ -7,8 +7,12 @@
 //
 //===----------------------------------------------------------------------===//
 
-#include "FormatTestUtils.h"
 #include "clang/Format/Format.h"
+
+#include "../Tooling/RewriterTestContext.h"
+#include "FormatTestUtils.h"
+
+#include "clang/Frontend/TextDiagnosticPrinter.h"
 #include "llvm/Support/Debug.h"
 #include "gtest/gtest.h"
 
@@ -11171,6 +11175,46 @@ TEST_F(FormatTest, FormatsTableGenCode) {
   verifyFormat("include \"a.td\"\ninclude \"b.td\"", Style);
 }
 
+class ReplacementTest : public ::testing::Test {
+protected:
+  tooling::Replacement createReplacement(SourceLocation Start, unsigned Length,
+                                         llvm::StringRef ReplacementText) {
+    return tooling::Replacement(Context.Sources, Start, Length,
+                                ReplacementText);
+  }
+
+  RewriterTestContext Context;
+};
+
+TEST_F(ReplacementTest, FormatCodeAfterReplacements) {
+  // Column limit is 20.
+  std::string Code = "Type *a =\n"
+                     "    new Type();\n"
+                     "g(iiiii, 0, jjjjj,\n"
+                     "  0, kkkkk, 0, mm);\n"
+                     "int  bad     = format   ;";
+  std::string Expected = "auto a = new Type();\n"
+                         "g(iiiii, nullptr,\n"
+                         "  jjjjj, nullptr,\n"
+                         "  kkkkk, nullptr,\n"
+                         "  mm);\n"
+                         "int  bad     = format   ;";
+  FileID ID = Context.createInMemoryFile("format.cpp", Code);
+  tooling::Replacements Replaces;
+  Replaces.insert(tooling::Replacement(
+      Context.Sources, Context.getLocation(ID, 1, 1), 6, "auto "));
+  Replaces.insert(tooling::Replacement(
+      Context.Sources, Context.getLocation(ID, 3, 10), 1, "nullptr"));
+  Replaces.insert(tooling::Replacement(
+      Context.Sources, Context.getLocation(ID, 4, 3), 1, "nullptr"));
+  Replaces.insert(tooling::Replacement(
+      Context.Sources, Context.getLocation(ID, 4, 13), 1, "nullptr"));
+
+  format::FormatStyle Style = format::getLLVMStyle();
+  Style.ColumnLimit = 20; // Set column limit to 20 to increase readibility.
+  EXPECT_EQ(Expected, applyAllReplacementsAndFormat(Code, Replaces, Style));
+}
+
 } // end namespace
 } // end namespace format
 } // end namespace clang
diff --git a/clang/unittests/Tooling/RefactoringTest.cpp b/clang/unittests/Tooling/RefactoringTest.cpp
index ff11aeae117..73da5a82cb2 100644
--- a/clang/unittests/Tooling/RefactoringTest.cpp
+++ b/clang/unittests/Tooling/RefactoringTest.cpp
@@ -418,6 +418,25 @@ TEST(Range, contains) {
   EXPECT_FALSE(Range(0, 10).contains(Range(0, 11)));
 }
 
+TEST(Range, CalculateRangesOfReplacements) {
+  // Before: aaaabbbbbbz
+  // After : bbbbbbzzzzzzoooooooooooooooo
+  Replacements Replaces;
+  Replaces.insert(Replacement("foo", 0, 4, ""));
+  Replaces.insert(Replacement("foo", 10, 1, "zzzzzz"));
+  Replaces.insert(Replacement("foo", 11, 0, "oooooooooooooooo"));
+
+  std::vector<Range> Ranges = calculateChangedRangesInFile(Replaces);
+
+  EXPECT_EQ(3ul, Ranges.size());
+  EXPECT_TRUE(Ranges[0].getOffset() == 0);
+  EXPECT_TRUE(Ranges[0].getLength() == 0);
+  EXPECT_TRUE(Ranges[1].getOffset() == 6);
+  EXPECT_TRUE(Ranges[1].getLength() == 6);
+  EXPECT_TRUE(Ranges[2].getOffset() == 12);
+  EXPECT_TRUE(Ranges[2].getLength() == 16);
+}
+
 TEST(DeduplicateTest, removesDuplicates) {
   std::vector<Replacement> Input;
   Input.push_back(Replacement("fileA", 50, 0, " foo "));